Micturition is critical to survival. Yet, little is known of how the motor pattern for micturition is chosen over others to ensure that voiding occurs at a safe place and time without interruption. Since, reactions to pain are also necessary for survival, understanding how an animal makes the choice between micturition and pain withdrawal movements will be particularly enlightening. In the first Aim, I will extend my preliminary findings that hind limb withdrawals are suppressed during micturition to determine whether withdrawals of body parts not involved in micturition are also suppressed. Neurons in the ventromedial medulla (VMM) are a major source of descending antinociceptive signals and may also modulate bladder afferent input and thus voiding behavior. In Aims 2 and 3, I will investigate the role of VMM neurons in modulating nociceptive withdrawals during micturition and in the modulation of bladder afferent input during continence. The data obtained in these experiments will provide an understanding at the cellular level of how an animal suppressing withdrawals and terminates continence when initiating voiding. [unreadable] [unreadable]